7-x*x=2.9

Solution for 7-x*x=2.9 equation:

7-x*x=2.9

We move all terms to the left:

7-x*x-(2.9)=0

We add all the numbers together, and all the variables

-x*x+4.1=0

Wy multiply elements

-1x^2+4.1=0

a = -1; b = 0; c = +4.1;
Δ = b2-4ac
Δ = 02-4·(-1)·4.1
Δ = 16.4
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-\sqrt{16.4}}{2*-1}=\frac{0-\sqrt{16.4}}{-2}
=-\frac{\sqrt{}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+\sqrt{16.4}}{2*-1}=\frac{0+\sqrt{16.4}}{-2}
=\frac{\sqrt{}}{-2}
$